利用部分传输序列减小MCCDMA系统的峰均比
Peak-to-Average Power Ratio Reduction in MC-CDMA Systems by Using Partial Transmit Sequence Schemes
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摘要: 为了更好地利用部分传输序列(PTS)来降低多载波码分多址(MC-CDMA)系统的峰均功率比(PAR),该文提出了对多路传输的子载波信号采用非均匀相邻分割方法。即在子载波频段上适当地减小低频和高频子载波块的大小,增大中间频率子载波块的大小可以进一步减小PAR。当中间频段数据块的大小是最低(或高)频段数据块的2倍时PAR达到最小,比均匀分割法下降0.2dB。针对旋转矩阵最优解的求解空间太大,该文同时采用遗传算法来减小计算的复杂度,仿真表明经过60代的进化可以达到最优解。Abstract: The un-uniform adjacent subcarrier partition method is proposed in order to reduce the Peak-to-Average power Ratio (PAR) of the signal in MultiCarrier-CDMA(MC-CDMA) systems by using Partial Transmit Sequence (PTS) scheme. That is reducing the number of subcarriers of high and low frequencies within a data block, and enhancing the number of subcarriers of intermediate frequencies if considering all subcarriers frequency as an band of frequency. When the number of subcarriers of the intermediate frequency within a data block is double of the number of subcarriers of the high (or low) frequencies, the PAR reduces 0.2dB comparing with that of the uniform partition. The Ganetic Algorithm(GA) is proposed in order to reduce the iterative number when the space of rotate-matrix is very big. By 60 generations evolution, the optimum value can be obtained. The results of simulation validate the proposed method.
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